The importance of family connection in both the horse and human world is a major theme throughout Misty of Chincoteague. It is visible in the opening chapters, when the first horses to arrive on Assateague survive by looking out for one another while the crew of the ship drown because all they can think about is money. The theme is explicitly introduced in Chapter 3, when Paul tells Maureen not to be sad about the Pied Piper coaxing the Phantom back into the herd because, just like people, horses are better when they are together.

The Beebe family and the Pied Piper’s family are the two major family units present in the book, and both are tightly bonded groups that care deeply for one another. Although the Beebe children’s background is never fully explained, they are raised in a nontraditional family, living with their grandparents while their parents are in China. Grandpa and Grandma Beebe love Paul and Maureen as their own and are proud of their ability to work independently to raise money to buy the Phantom. Although they are both gruff in demeanor, Grandpa and Grandma consistently support their grandchildren as well as each other.